1. Field of the Invention
The present invention relates to a coil device, and more specifically, it relates to a coil device provided with a plurality of coils at a single core.
2. Discussion of Background
A circuit which is achieved by connecting a plurality of coil devices being independent of one another is employed in various types of circuit apparatuses. For instance, a circuit having a common mode choke coil connected to the secondary winding of a transformer is employed in transmission apparatuses such as a LAN apparatus.
In a standard manufacturing process of a prior art circuit, a transformer and a common mode choke coil are manufactured separately and therefore mounted onto a circuit board separately. Not only does this require numerous mounting steps, but also limits the degree to which high density mounting is possible since a large area on the circuit board for mounting these parts is occupied.